Safety Precaution - Mitsubishi Electric Mr.Slim PKH-P3FALH Technical & Service Manual

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SAFETY PRECAUTION

Cautions for using with the outdoor unit which adopts R407C refrigerant.
· Do not use the existing refrigerant piping.
-The old refrigerant and refrigerant oil in the existing piping contains a large amount of chlorine which may cause the refriger-
ant oil of the new unit to deteriorate.
· Do not use copper pipes which are broken, deformed or discolour .
-In addition, be sure that the inner surfaces of the pipes are clean, free of hazardous sulphur and oxides, or have no dust /
dirt, shaving particles, oils, moisture or any other contamination.
-If there is a large amount of residual oil (hydraulic oil, etc.) inside the piping and joints, deterioration of the refrigerant oil will
result.
· Store the piping to be used during installation indoors and keep both ends of the piping sealed until just before
brazing. (Store elbows and other joints in a plastic bag.)
-If dust, dirt, or water enters the refrigerant cycle, deterioration of the oil and compressor trouble may result.
· Use ester oil, ether oil or alkyl benzene (small amount) as the refrigerant oil to coat flares and flange connections.
-The refrigerant oil will degrade if it is mixed with a large amount of mineral oil.
Use liquid refrigerant to fill the system.
-If gas refrigerant is used to fill the system, the composition of the refrigerant in the cylinder will change and performance
may drop.
· Do not use a refrigerant other than R407C.
-If another refrigerant (R22, etc.) is used, the chlorine in the refrigerant may cause the refrigerant oil to deteriorate.
· Use a vacuum pump with a reverse flow check valve.
-The vacuum pump oil may flow back into the refrigerant cycle and cause the refrigerant oil to deteriorate.
· Do not use the following tools that are used with conventional refrigerant.
(Gauge manifold , charge hose, gas leak detector, reverse flow check valve, refrigerant charge base, vacuum gauge,
refrigerant recovery equipment)
-If the conventional refrigerant and refrigerant oil are mixed in the R407C, the refrigerant may deteriorated.
-If water is mixed in the R407C, the refrigerant oil may deteriorate.
-Since R407C does not contain any chlorine, gas leak detectors for conventional refrigerant will not react to it.
· Do not use a charging cylinder.
-Using a charging cylinder may cause the refrigerant to deteriorate.
· Be especially careful when managing the tools.
-if dust, dirt, or water gets in the refrigerant cycle, the refrigerant may deteriorate.
· Don't use the drier which is sold in the field.
-The drier for R407C refrigerant is Pre-attached to outdoor unit refrigerant circuit.
-Some drier in the field are not in conformity with R407C refrigerant.
[1] Service tools
Use the below service tools as exclusive tools for R407C refrigerant.
No. Tool name
1
Gauge manifold
2
Charge hose
3
Electronic scale
4
Gas leak detector
5
Adapter for reverse flow check
6
Refrigerant charge base
7
Refrigerant cylinder
8
Refrigerant recovery equipment
Specifications
·Only for R407C.
·Use the existing fitting SPECIFICATIONS. (UNF7/16)
·Use high-tension side pressure of 3.43MPa·G or over.
·Only for R407C.
·Use pressure performance of 5.10MPa·G or over.
·Use the detector for R407C.
·Attach on vacuum pump.
·For R407C ·Top of cylinder (Brown)
·Cylinder with syphon
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